Fatigue of Martensite-Ferrite High Strength Low-alloy Dual Phase Steels.

Abstract

Fatigue tests were carried out with as-rolled and heat-treated Si-Mn-Cr-Mo martensite-ferrite dual-phase steels at room temperature in air and 3.5 % NaCl solution. The effects of duplex microstructural morphologies, martensite contents and environmental conditions on fatigue stress-life, cyclic deformation behavior, fatigue crack initiation and near-threshold fatigue crack growth were investigated. The influence of prestrain and ageing on fatigue threshold was also studied.